The following U.S. Patents are incorporated herein by reference and provide background information regarding the present disclosure.
U.S. Pat. No. 8,435,090 discloses a marine drive having a gear case that houses a vertical driveshaft that rotates a generally horizontal propulsor shaft in a forward direction upon operational engagement with a forwardly rotatable gear and a rearward direction upon operational engagement with a rearwardly rotatable gear. A lubricant exclusion cover is disposed between the forwardly and rearwardly rotatable gears so as to limit churning of lubricant by at least one of the forwardly and rearwardly rotatable gears.
U.S. Pat. No. 8,616,929 discloses a vessel propulsion apparatus including a second shaft that is inserted in a first driven gear and in a second driven gear, that is connected to a dog clutch, and that is arranged to undergo a thrust. The vessel propulsion apparatus includes a first bearing disposed between the first driven gear and the second shaft, a second bearing disposed between the second driven gear and the second shaft, and a case to which a thrust applied to the second shaft is transmitted via the first bearing and the first driven gear or via the second bearing and the second driven gear. The vessel propulsion apparatus includes an adjusting member disposed between the second shaft and at least one of the first driven gear and the second driven gear and arranged to apply a preload onto the first bearing and the second bearing.
U.S. Pat. No. 9,174,715 discloses an apparatus for a changing gear in a marine propulsion system. A cam rotates about a first axis with a shift shaft. The cam has a body and an arm that radially extends from the body with respect to the first axis. A cam follower moves parallel to a second axis that is perpendicular to the first axis to cause movement of a clutch, thereby enacting a gear change. The cam follower defines a pocket that is elongated with respect to the second axis and a recess that extends from the pocket along a third axis that is perpendicular to the first and second axes. The cam is disposed in the pocket and the arm extends into the recess. During a constant rotation of the shift shaft in a first direction about the first axis, the cam follower moves with respect to the second axis to enact the gear change and also dwells with respect to the second axis.
U.S. Pat. No. 9,896,177 discloses a marine drive comprising an internal combustion engine that effectuates rotation of the driveshaft, a propulsor driven into rotation by the driveshaft so as to effect thrust, and a transmission that shifts amongst a forward gear, a reverse gear, and a neutral gear. The marine drive has a gear case housing on the bottom portion and a driveshaft housing around the driveshaft and positioned between the internal combustion engine and the gear case housing. The marine drive has a shift rod rotatable about its own axis, wherein rotation of the shift rod about its own axis shifts the transmission amongst the forward gear, the reverse gear, and the neutral gear. The marine drive also comprises an actuator positioned in the driveshaft housing that effectuates the rotation of the shift drive about its own axis.